초록

Delayed coking process in which improved liquid yield is achieved by varying the rate at which the heavy feedstock is fed to the coke drum. Tandem operation of two active coking drums is disclosed which permits feedrate variation without change of load on furnace.

대표청구항 ▼

A process for the delayed coking of a heavy hydrocarbon oil feedstock in an apparatus comprising a first and second coker furnace and a first and second active coking drum, each of said coking drums having a processing capacity for C ft3 of heavy hydrocarbon oil feedstock preheated to coking tempera

A process for the delayed coking of a heavy hydrocarbon oil feedstock in an apparatus comprising a first and second coker furnace and a first and second active coking drum, each of said coking drums having a processing capacity for C ft3 of heavy hydrocarbon oil feedstock preheated to coking temperature by said furnaces, each of said furnaces being capable of providing a continuous flow of said preheated feedstock at a fixed flow rate of V ft3/hr such that at a total drum-fill time of t hours each provides a flow (V×t)=C, which process comprises: (a) providing conduit and valve means whereby the combined output of said first and second furnace is unequally proportioned between said first and second active coking drums; (b) initiating the fill of said first active coking drum at flow rate V1 which is greater than V but less then 2V and maintaining said flow for 0.5 t hours while passing the remainder of said combined output to said second active coking drum whereby completing its fill; and, (c) completing the fill of said first active coking drum at a flow rate of V2=2V-V1 while initiating the fill of said second active coking drum at flow rate V1.